If you spend very much time on the web reading about infrared sauna and weight loss, you will very soon run across a claim that the heat of the sauna “melts” fat cells. Melt fat cells? The image is kind of poetic. But the words are marketing copy. Fat cells don’t melt. They can die, through some form of lipolysis, but they don’t melt.
Infrared sauna does not kill fat cells. You come out of the sauna cabinet with the same number of fat cells you went in with. But infrared sauna can help to shrink fat cells. In this way, it can support weight loss. If you want to use infrared sauna for weight control, it helps to understand the four mechanisms by which infrared sauna can help to shrink your fat cells.
First of all, note that there’s no magic to any of this. The way to shrink fat cells is to go into calorie deficit; that is, you need to expend more calories than you take in. When you do that, you aren’t providing enough glycogen (which comes from food) needed to fuel your body at its current weight. So your body begins to drain lipids from your fat cells to make up the difference. What we’re looking for, then, are the ways in which infrared sauna helps to promote calorie deficit.
1. The Mechanism of Sweating
At the cellular level, sweating burns calories: about 0.586 calories per gram of perspiration. This is not water loss; it is energy expenditure over and above the water loss. For every pint you sweat, you burn about 260 calories. Sweat two pints and you’ve burned 520 calories, or about one seventh of a pound. One seventh of a pound may not be the kind of weight loss you’re looking for, but it can add up, particularly if you’re consistent in using the sauna. If you’re not seriously overweight, regular sauna could be enough to help you control your weight.
2. Blood Ghrelin Concentration
According to a 2003 study (PDF) out of Kagoshima University, sauna treatments increase blood concentration of ghrelin, the hunger prompter. For patients of normal weight, the increased concentration of ghrelin increases appetite. But the same study found that this effect doesn’t operate in obese patients. In fact, for these patients, sauna seems to lead to healthier eating habits. The study featured an obese patient whose body fat went from 46% to 35% in ten weeks. This effect needs a lot more study, but it does suggest that sauna has a direct effect on appetite in obese people, which can help them maintain a calorie deficit. So if you are seriously overweight, regular sauna sessions could help you control your weight.
One of the effects you may notice when you’re in a sauna is an increased heart rate. Most researchers compare a sauna session to a moderate workout in terms of cardiovascular benefit. This increased heart rate persists after you’ve left the sauna. Increased heart rate means increased metabolism, which is another way of saying burning more calories. The metabolic effect of sauna has not been studied very much, and I have been unable to find any measures of how long the increased metabolism persists after the sauna session. But, at some point, the cardiovascular benefit of regular sauna must contribute to calorie deficit and therefore weight control.
A sauna session relaxes you, and the link between stress and weight gain is very well known. That’s not the same as saying there’s a link between relaxation and weight loss, but at the very least, de-stressing yourself helps to preserve calorie deficit.
So, if you’re trying to lose weight through diet and exercise, consider regular infrared sauna sessions as a way of locking in your calorie deficit. It’s not going to melt your fat cells, but it will help you to keep them from growing excessively. Book a session today.